A conventional twine tying or knotter arrangement of a rectangular baler includes a plurality of knotter assemblies or devices mounted in side-by-side relationship along a knotter drive shaft, with the number of knotter assemblies being equal to the number of loops of twine to be tied around a bale, and with the number of loops of twine being dependent upon the size of the bale being produced. Each knotter assembly includes a knotter frame, which carries various knotter components, and a knotter drive gear. The knotter frame is either mounted on the knotter drive shaft adjacent an associated knotter drive gear or mounted on a hub of the associated drive gear, the latter being an intermittent gear having gear segments respectively located for meshing with driven gears of selected knotter components, and having cam surfaces for engaging cam rollers or followers for controlling movement of other knotter components. In both cases the knotter frame remains fixed while the knotter drive shaft or drive gear hub rotates freely within a sleeve or eye of the knotter frame. Correct positioning between the drive gear and driven components carried by the knotter frame is achieved by using shims, spacers, and other devices for retaining an adjusted position. U.S. Pat. No. 6,164,197 discloses an arrangement wherein the knotter frame is mounted on an elongate hub of the knotter drive gear and is held in an adjusted location relative to the knotter gear by a nut threaded onto the free end of the hub. In addition, these balers are normally provided with a device for adjusting the lateral space between adjacent knotter assemblies on the knotter drive shaft. Such adjustment is necessary so that the knotter assemblies are in proper alignment with the twine-delivery needles and the knotter table.
One known way of adjusting the lateral spacing between adjacent knotter assemblies is done by providing at least a pair of shims or spacers in the form of tapered rings mounted in engagement with each other on the drive shaft between the knotter assemblies. Desired spacing of the knotter assemblies is achieved by releasably securing the tapered rings together in desired angular positions relative to each other by using set screws or by using wire ties that are woven between radial pegs respectively carried by the pair of tapered rings. Such an arrangement for securing the rings together is not easy to release and reapply nor is it easy to turn the rings relative to each other once released, especially when the parts have been operating in the dirty environment present on a baler. Furthermore, the tapered shims or spacers are somewhat costly to manufacture. U.S. Pat. No. 4,022,121 shows an example of tapered rings, which are retained in adjusted positions by set screws and are provided with radial holes into which a tool may be inserted for rotating the rings relative to each other on the knotter drive shaft.